Barb and Gary Rudolph are experienced water gardeners from Petersburg, VA.

This article applies to:

The Ways of Water by Barb and Gary Rudolph

Large-leaved plants, such as water lilies, help shade the water garden,
which can improve conditions for fish and other plants during the heat of summer.

A water garden is exciting in every season, but ponds and streams are most beautiful and dynamic in the summer. The water and its surroundings teem with life — thriving plants, growing (and always hungry) fish, serenading frogs, colorful birds and industrious insects. The often brutal heat in the South drives many folks indoors to air-conditioned spaces but, as a committed gardener, what is more inviting on a sultry day or night than the sights and sounds of water?

To fully enjoy your water garden and its inhabitants, proper maintenance is a must. Most tasks associated with maintenance can be performed in the morning — we do many of these things before going to work — so you won’t have to break a sweat. Use the information in this article to design a routine that is comfortable and convenient for you and your family. Most importantly, view this as an opportunity to get better acquainted with this remarkable ecosystem.

Water Quality is the Key

Maintaining good water quality is the foundation for a healthy water garden. When water quality is compromised, plants, fish, equipment and the physical structure of the water garden will develop problems. To keep your water garden’s elements in top shape, it is important to understand how the water’s condition affects, and is affected by, its contents and surroundings.

Many variables contribute to a stressful water environment — heat, other weather conditions, water loss and replacement, water circulation, gardening practices, equipment condition, plant growth, fish population and “visitors” (human and animal). Some of these variables are beyond our control, but knowing how to deal with each of them is critical.

Critical Factors for Water Gardens

• Heat: Water temperature rises when air temperatures become uniformly high. Some tropical water plants (such as water hyacinths) will experience seemingly exponential growth spurts. This may be too much of a good thing.

In small water features, long spells of very hot weather can be a particular problem for fish; in a large pond, the impact is less extreme. Thankfully, large-leaved plants, such as water lilies and lotuses, mitigate the effects of heat by shading much of the water’s surface.

• Other weather conditions: Driving summer thunderstorms produce rapid runoff and erosion. Soil surrounding the water garden may be washed into the water if the perimeter is not secure, muddying the water and also adding excess organic material and possibly garden fertilizers.

High winds can damage plants in and around the pond, and drop leaves and branches in the water. Severe electrical storms, on occasion, will cause water near the surface to become extremely turbulent and oxygen-depleted, which endangers fish.

• Water loss and replacement: In the summer, water evaporation is inevitable. This makes it especially important to assure that your water feature is free from leaks, undermined edges and other structural problems that can cause water loss. Rainfall is the best source of water replacement; rely on it as much as possible. In periods of drought, supplemental water is needed, however.

If you raise fish and your source of water is treated by the municipality, it is critical to amend significant water additions with products that neutralize chlorine and chloramine.

This powerful submersible pump was recently replaced when it began operating erratically. If possible, it will be rebuilt as a backup.

• Water circulation: Plants and fish need oxygen to live. Stagnant water is also unattractive and encourages algae growth and mosquito breeding. In all but the smallest water features, it is vital to have some means of circulating or moving the water.

Pumps come in many sizes and are reasonably priced and easy to install. For water gardeners who raise large numbers of fish, even greater water circulation is needed to adequately oxygenate the water. The usual aeration solutions include fountains, spitters and waterfalls.

• Gardening practices: Practices you consider routine or necessary in your “land” garden can have unforeseen effects on the water garden. Fertilizers, herbicides and pesticides applied to the garden — no matter how carefully — may be transported to the water garden by rain or wind.

While we thought high-pressure spraying of insecticides into the trees was great when it eliminated mosquitoes from our daughter’s outdoor wedding nine years ago (pre-water garden), it’s not a practice we would currently consider — it would certainly condemn many beneficial insects and very likely endanger the fish.

• Equipment condition: The mechanics of your water feature are easier to maintain at peak capacity when you take care of water quality. Then, in turn, the equipment is able to do its part to clean and circulate the water. Some sources say a weekly cleaning skimmers and filters is adequate. This is not true if your surroundings include trees and shrubs, or even if there are many windy days.

Streams and waterfalls can improve your water garden’s health. They oxygenate the water,
counter algae growth and discourage mosquito breeding.

Check these equipment components daily, reducing the frequency if your situation warrants it. It is also a good idea to periodically examine external submerged pumps to ensure that their operation is not impeded by debris such as sticks, leaves and, at our house, pine cones.

Parrot’s feather, a rooted floater and reeds capture leaf debris in the pond. The debris can easily be removed by hand or with a net.

Erosion has washed away some of the gravel covering the rubber liner (foreground). Restoring the gravel will protect the liner from sun damage.

Good water quality spells summer enjoyment for grandchildren and water gardeners alike!

• Plant growth: The five types of water garden plants (oxygenators, true floaters, rooted floaters, marginal and bog) serve as filters, oxygen producers, temperature regulators and aquatic life habitat. For example, wholly submerged plants, such as anacharis, provide valuable oxygen for other plants and fish. True floaters — water lettuce, for example — have roots that dangle below the surface and capture nutrients that would otherwise cloud the water. Bog plants act as a natural filter and barrier against soil invading the water garden. These plants’ beneficial contributions may, however, be nullified if the water gardener does not regularly remove spent stems, leaves and flowers from aquatic plants and control algae growth as necessary.

• Fish population: Keeping fish is one of the greatest delights of water gardening, but it can also become a fairly costly and time-consuming hobby for koi enthusiasts. In theory, fish can survive without supplemental feeding — and indeed, they should only be fed in the warm seasons — but that takes the fun out of raising them for many of their admirers.

A key point to consider is that commercial fish food has an impact on water quality both before and after it is consumed. Use common sense when stocking your water feature to avoid including so many fish that maintaining good water quality is dependent upon not only mechanical systems but chemical additives as well.

• Visitors (humans and animals): Summer can make the water garden irresistible to children and animals. It’s obvious that, for safety reasons alone, you don’t want young children to be around water of any depth without careful supervision. Wandering dogs may visit for a drink and even a dip, which can wreak havoc on water plants, liners and water clarity. Wildlife may prey on fish and plants.

Physical barriers can exclude some unwanted visitors, but they may not deter avid “fishermen,” such as raccoons and herons. A pond intended for people to swim or lounge in should be designed with additional filtration equipment (e.g. an ultraviolet sterilizer) to control bacteria and fungi.

Remember: Put water quality first on your to-do list. Making the “water” in water gardening the focus of your attention will yield many benefits. Attentive maintenance addresses unforeseen problems when they crop up and prevents the water quality problems you are able to anticipate. There are few reasons to reach for the chemicals, or work yourself to death, when you are an alert water gardener!

• Service pumps — the water garden’s workhorse — as recommended by the manufacturer.

• Replace other equipment components, such as UV bulbs, as needed.

• Ease the load on your mechanical equipment by regularly skimming the water manually, using proper cultural practices for aquatic plants and fish, and employing natural/biological filtration measures.

Plant Care

• Prevent algae growth by maintaining an optimum balance of plants and fish. If algae growth does occur, manually remove/control before relying on chemical additives.

• Remove spent flowers, leaves and stems on water plants regularly.

• In this prime growing season, fertilize water lilies, lotuses and other plants monthly using products designed specifically for water plants.

• Prune or divide aquatic plants that have outgrown their containers.

• Remove rapidly multiplying tropicals, such as water hyacinth and water lettuce, before they overtake your water feature, and share the excess plants with other water gardeners.

• Never discard these plants or other unwanted aquatic life in natural bodies of water where they can disrupt the ecosystem.

Fish Care

• Be judicious in feeding fish; do not provide more food than they can consume in five or fewer minutes.

• Observe fish carefully, and isolate any who appear to be diseased to prevent spread to others in the population. Seek advice from experts if you are unsure of the problem and its possible cure.

• Use growth food, if desired, only in the warmest months when fish are active and can adequately digest a higher protein diet.

• Keep a close eye on population growth; share this year’s spawn with others if the additional fish will tax your water garden’s health.

• If you are still stocking your pond, introduce new fish gradually and in small numbers.

• Protect vinyl and rubber liners by keeping all exposed areas covered with rocks or gravel to avoid sun damage to the material.

• Ensure rock borders around the water garden are stable and secure.

Chemical Additives

• Above all, use extreme caution when resorting to chemical solutions to water gardening problems. Read instructions carefully to ensure that the desired product is compatible with the living contents of your water garden — plants, fish, amphibians, snails, etc.

• Know the volume of your water feature so that the proper amount of product is applied. If in doubt about water volume, be cautious and use a lesser concentration of chemical additives.

• Do not use chemical additives repeatedly to treat cultural problems; instead, look carefully for underlying causes and seek professional advice if necessary.

The views and opinions expressed in this article are those of the author alone and do not necessarily reflect the views or opinions of State-by-State Gardening, its parent company or affiliates. The author is solely responsible for all content. Our articles are only meant to educate and entertain our readers. We are not medical professionals and cannot recommend the ingestion or topical application of any herbal remedy, poultice, tea, etc. Please consult a medical professional before ingesting any plant.